The invention relates to an axially damping elastomer bearing, in particular for a motor vehicle, according to the preamble of claim 1.
Axially damping elastomer bearings for motor vehicles are known in many different forms. The key components of an axially damping elastomer bearing are an elastomeric support spring and a housing part which surroundingly accommodates this. In an installed state in which it is built into the motor vehicle, water-collecting geometrical regions are frequently formed between the elastomeric support spring and the housing part. Water-collecting geometrical regions should be understood here to mean cavities or contours in which liquids, in particular water, can collect when the motor vehicle is essentially standing vertically. Spray water frequently collects in these water-collecting geometrical regions, for example if the axially damping elastomer bearing is in the form of an engine bearing mounted in a relatively low position in relation to the roadway. Water from flooded roads or puddles can also collect in the water-collecting geometrical regions when driving. In addition, during a car wash, water can also collect in water-collecting geometrical regions of axially damping elastomer bearings which are mounted in more elevated installation locations within the motor vehicle. This applies for example to suspension strut support mounts.
If water which has collected in the water-collecting geometrical regions freezes, this frequently leads to a significant impairment of the damping and acoustic behaviour of the axially damping elastomer bearing. In addition, the elastomer bearing can also be damaged through freezing water, for example through bursting of the housing part holding the elastomeric support springs.
It is known, from the prior art for housing parts of axially damping elastomer bearings to be provided with drainage openings at the lowest points of the water-collecting geometrical regions in order to allow the water-collecting geometrical regions to be drained. Such a drainage outlet is for example known from DE 601 11 208 T2.
For cost reasons, the drainage openings are usually introduced into the housing parts by means of equipment which is used to manufacture the housing parts themselves. This can for example be a die-casting tool, if the housing part is designed as a die-cast part. It is known from the prior art for drainage openings to be formed in housing parts which are designed as die-cast parts by means of so-called sliders. The sliders thereby have an operating direction which is oriented roughly at right angles to a demoulding direction of the die-casting tool.
The object of the invention is, through a simplified manufacturing method, to provide an economical axially damping elastomer bearing with at least one drainage opening.